Telecommunication network

Abstract: In known telecommunication networks users (4-1 ... 4-M) of a facsimile machine (2-1 ... 2-N) are not identified. As a result, no evidential value relating to the identity of the sending user (4-3) or the identity of the receiving user (4-M) and the originality of the contents of the facsimile message can be derived from messages sent by facsimile machines (2-1 ... 2-N). A telecommunication network (1) according to the invention comprises identification means (3) for processing a user identification signal (USID). The identification means (3) are also arranged for producing a message (40) encrypted according to a digital signature method, which message states that a facsimile message has been exchanged between a sending user (4-3) and a receiving user (4-M). The message (40) is produced in a machine-readable code. Since this message (40) can only be generated by the identification means (3) and the contents cannot be modified unnoticed later on, this is proof of an exchange of a facsimile message between the sending user (4-3) and the receiving user (4-M).

Description: The invention relates to a telecommunication network comprising at least a facsimile machine. A facsimile machine to be used in such a telecommunication network is described in French Patent Application 8803861 corresponding to the published document FR-A-2 660 135. This facsimile machine comprises a PROM memory whose contents cannot be changed by the user, in which the data of the facsimile machine as well as the number of the telephone line to be used for facsimile transmission are stored. When a facsimile is sent, these data plus day, time and information about the receiving facsimile machine are printed on the original message by the sending facsimile machine. All this information is sent along with the message to the receiving facsimile machine, so that it is also printed on the received facsimile. As a result, both parties have information that a specific message has been exchanged between a sending facsimile machine and a receiving facsimile machine on a certain day and at a certain moment of time. A drawback of this method is that there is no identification of a user of the facsimile machine such as there is an identification of the receiver and the sender of a parcel in the case of registered post. As a result, no evidential value relating to the identity of the sender, the identity of the receiver and the originality of the contents of the facsimile message can be derived from messages sent by facsimile machine. It is an object of the invention to provide a method in which there is a possibility to have a user of a facsimile machine identified by an independent body. Therefore, the present invention provides a certification method for facsimile devices in a telecommunication system comprising at least a sending facsimile device, a receiving facsimile device and an independent body, in which certification method at least the contents of a facsimile message and/or the moment of transmission of the facsimile message and/or a transmission event are certified by a digital signature and an unforgeable receipt or certificate in machine readable form is provided by the independent body and in which certification method users of both the sending and the receiving facsimile device are identified by the independent body. Such a user identification signal is personal and can therefore be entered only by the user. The identification means form part of the telecommunication network and are therefore managed by an independent body. The identifying of a user of the facsimile machine by an independent body provides a facsimile service that can be compared with registered post. A network in which the user of a peripheral device is identified is known per se from Patent Specification WO 92/09161. However, a user of a first terminal is then identified by a user of a second terminal. The users of such a telecommunication network all receive a secret personal key and a public key for the coding and decoding of messages. However, each user is to have computer equipment then. The invention will be further explained with reference to a drawing in which: Fig. 1 shows a telecommunication network according to the invention, Fig. 2 shows the identification procedure according to an advantageous embodiment of the invention, Fig. 3 gives an example of a preprinted form which is completed by the sending user and sent to the identification means, Fig. 4 gives an example of a message encrypted with a secret key by the identification means and containing a user request signal, Fig. 5 shows a further embodiment for the identification means shown in Fig. 1, and Fig. 6 shows a personal list for user identification signals. Fig. 1 shows a telecommunication network 1 according to the invention. The telecommunication network 1 comprises a plurality of facsimile machines 2-1 ... 2-N, and identification means 3 for identifying users 4-1 ... 4-M of the facsimile machines 2-1 ... 2-N. Users may be both persons, legal entities such as businesses, and devices working under the control of persons. The number of users M need not be equal to the number of facsimile machines N, because there may be a plurality of users 4-1 ... 4-M per facsimile machine 2-1 ... 2-N utilizing the telecommunication network 1 according to the invention. The network 1 according to the invention comprises the identification means 3 which make it possible to identify facsimile machine users. The identification means 3 are located in an exchange in the network or are accommodated in a decentralized manner at the users 4-1 ... 4-M. The number of identification means 3 located in a telecommunication network 1 are not subject to limitation. The identification means 3 are to be installed by an independent body, preferably the network manager. This independent body registers all the system users 4-1 ... 4-M who wish to make use of the facility for sending or receiving authenticated facsimiles. For this purpose, these users 4-1 ... 4-M are to submit a request to the network manager. The network manager registers the personal data and the number of the facsimile machine 2-1 ... 2-N, as required. The network manager sends to the user 4-1 ... 4-M a personal generator 7 such as the Digipass generator produced by Digiline or a personal list (see Fig. 6) of associated codes of user request signals USREQ and user identification signals USID. Fig. 2 shows the identification procedure according to an advantageous embodiment of the invention. This Figure shows the steps necessary to allow a sending user 4-3 belonging to facsimile machine 2-2 to send a registered message to a receiving user 4-M belonging to facsimile machine 2-N. The Figure is subdivided into 5 columns. Each column is headed by the person or machine carrying out the step involved. For example, SR denotes sending user, SF sending facsimile machine, IM stands for identification means, RF stands for receiving facsimile machine and RR stands for receiving user. In step 101 the sending user 4-3 completes a preprinted form 30. Fig. 3 shows an example of the preprinted form 30 on which the sending user 4-3 fills in in mark code the data of the receiving user 4-M to whom the message is to be sent and what services are to be used. Such a preprinted form 30 is sent to the users 4-1 ... 4-M of the system by the independent body managing the identification means 3. The form 30 has a certain layout because it is to be read out automatically by the identification means 3. Box 31 states the data of the independent body and information about the type of form 30. Box 32 states the facsimile number of the identification means 3 and the number of the public key PK. Box 33 states in a preprinted layout the name of the sending user 4-3 in ordinary text and his/her facsimile number in mark code. Box 34 contains a preprinted layout for filling in the name of the receiving user 4-M and a preprinted part for filling in the facsimile number of the receiving user 4-M in mark code. Box 35 specifies a plurality of services. If the sending user 4-3 wishes to employ one of the services, he/she is to tick off a box behind this service. Examples of such services are: The sending user 4-3 obtains an acknowledgement of receipt (Envoi recommandé avec accusé de réception). The contents of the message are stored by the identification means 3 for a certain period of time (Archivage durant trois mois), and so on. The telecommunication network may also have the option to indicate by means of speech, in lieu of the form 30, to whom the registered facsimile message is to be sent and what services are desirably employed. In that case the identification means 3 are to be arranged for speech recognition. As an alternative to speech, the DTMF keys on the facsimile machine can be used to indicate this. After the data of the sending user 4-3, the data of the receiving user 4-M and the services requested from the identification means 3 by the sending user 4-3 have been filled in, this form 30 along with the message to be sent is sent to identification means 3 by the sending facsimile machine 2-2 in step 102 (SND = send). These identification means 3 receive the data in step 103 (RCV = receive), store the contents of the registered message in step 104 (STR = store) and generate a user request signal USREQ for the sending user 4-3 in step 105 (USREQ = user request). In the embodiment described here the user request signal (USREQ) is a 6-digit number. In step 106 (SK = secret key) a number of data relating to the sending user 4-3, the receiving user 4-M and the date and time as required, are encrypted with a secret key SK only known to identification means 3. In step 107 (SND) the data encrypted in step 106 are sent in directly readable form and in encrypted form to the sending facsimile machine 2-2 along with the user request signal USREQ. This signal is received in step 108 (RCV) and printed by facsimile machine 2-2. Fig. 4 gives an example of a message 40 sent by the identification means 3 to the facsimile machine 2-2 of the sending user 4-3 or, as will be explained hereinafter, to the facsimile machine 2-N of the receiving user 4-M, which message contains the details of both sending user 4-3 and receiving user 4-M, date and time in ordinary text and in code, and shows the user request signal USREQ in this basic example by way of a number (281803). Since this message 40 is also used for facsimileing back the user identification signal USID, this message has a predetermined layout. Box 41 shows the information about the independent body and information about the type of message 40. Box 42 mentions the user request USREQ both in ordinary digits and in mark code. Box 43 is a preprinted box for filling in the user identification USID both in ordinary digits and in mark code. Box 44 contains the information of the sending user 4-3, the information of the receiving user 4-M, the services requested, the date and moment of time in ordinary text. The number of the public key PK of the identification means 3 is also mentioned here. Box 45 contains the information of box 44 with the secret key SK of the identification means 3 in coded form. In this embodiment this information is dot-coded. This code contains redundant information. As a result, the information is still decodable even if a small number of dots are misplaced. In the event of a dispute, this information can be decoded with the public key PK. This makes it possible to verify whether the message 40 has been sent by the identification means 3 and whether nothing has changed in the original contents of the message. In box 46 part of the contents of the registered message is printed. Consequently, a specific amount of reliability about the contents is already built in. Absolute certainty can be obtained if the contents of the registered message are stored by the identification means 3. As will be further described with reference to the embodiment shown in Fig. 2, the identification means 3 will send a message similar to message 40, but not including a user request signal USREQ, to the facsimile machine 2-2 of the sending user 4-3 as an acknowledgement of receipt. The sending user 4-3, having received a generator 7 from the independent body managing the identification means 3, enters the 6-digit user request USREQ in generator 7 which generates the 6-digit user identification signal USID belonging to the sending user 4-3. If the user has no generator 7, he/she fills in a digit code based on the personal list 6. This USID is filled in in mark code in step 109 (USID = user identification) in response to the message 40 sent in step 108 (RCV). This message 40 can be used by the sending user 4-3 as proof of a registered message, because it may show by means of a deciphering of the encrypted message with the public key PK that message 40 has been sent by the identification means 3. In step 110 (SND) the message 40 now carrying the user identification USID of the sending user 4-3 is sent to the identification means 3 by the sending facsimile machine 2-2. In step 111 (RCV; CNTRL = control) these identification means 3 verify the identity of the sending user 4-3 on the basis of the sent user identification signal (USID). Subsequently, in step 112 (USREQ) the identification means 3 determine a user request signal USREQ for the receiving user 4-M. This may be a 6-digit number specific of the receiving user 4-M corresponding to the user request signal USREQ of the sending user 4-3. In step 113 (SK) a number of data relating to the identity of the sending user 4-3, the identity of the receiving user 4-M and the date and moment of time, as required, are encrypted with the secret key SK by the identification means 3. In step 114 (SND) the data encrypted in step 113 (SK) are sent both in directly readable form and in encrypted form to the receiving facsimile machine 2-N along with the user request signal USREQ and the facsimile message stored in step 104. In step 115 (RCV) user 4-M receives this signal. In step 116 (USID) the receiving user 4-M determines the user identification USID in response to the received user request signal USREQ. This user identification is again a 6-digit number in this embodiment. This number is determined (since user 4-M has no generator 7) with the aid of a personal list 6 issued upon registration to the receiving user 4-M by the independent body, which list states what user identification USID is to be given as a response to a certain user request signal USREQ. This user identification USID is to be filled in in mark code in message 40 sent in step 116 (USID ). This message 40 has an identical layout to the message 40 sent in step 107 to the sending user 4-3, but may have slightly different contents. The message may be used by the receiving user 4-M as proof that the sending user 4-3 has sent a registered message to him/her on a specific day and at a specific moment of time. In step 117 (SND) the message 40 is sent to the identification means 3 by the receiving facsimile machine 2-N. These identification means 3 verify in step 118 (RCV; CNTRL) the identity of the receiving user 4-M. If the identification means 3 have not received within a certain period of time the message 40 containing the user identification USID of the receiving user 4-M, a new request for the sending of the user identification signal USID is made to the receiving facsimile machine 2-N. If this request is not responded to within a certain period of time, the facsimile message is sent to the receiving user 4-M by registered post. Preferably, the cost of this is to be incurred by the receiving user 4-M. If the sending user 4-3 has requested by means of form 30 to be informed of the reception of the registered message by the receiving user 4-M, the identification means 3 code a suchlike message with the secret key SK in step 119 (SK). In step 120 (SND) this message is sent to the sending facsimile machine 2-2 which receives this message in step 121 (RCV). This procedure is used for acknowledgement of receipt of the message by the receiving user 4-M to the sending user 4-3. For a person skilled in the art it is obvious that the invention is not restricted to the protocol represented in Fig. 2, but may easily be extended or modified. By analogy with the registered post, for which the sender is not always identified but only if the sender wishes to have an acknowledgement of receipt the identification of the sending user 4-3 may be dispensed with, for example. As a result, the steps 105 and 109 to 111 incl. in Fig. 2 are not carried out. Each user 4-1 ... 4-M may be supplied, as desired, with a personal generator 7 generating the user identification signal USID in lieu of the personal list 6 with coherent code numbers. The user request USREQ and the user identification USID naturally need not be numbers but may contain any arbitrary sign such as pure text. Other identification methods too can be easily incorporated in the invention. For example, it is possible, to supply the sending user 4-3 with a dynamic password generator which generates user-specific passwords (USID's) in response to time, which passwords are filled in directly on form 30 by the sending user 4-3 in step 101 (FMLR; MSSG). In that case the identification means 3 need not generate a user request signal USREQ when the sending user 4-3 wishes to send, and may directly change to verifying the identity by means of a received USID signal. Consequently, steps 105 to 111 incl. in Fig. 2 are omitted. The reliability of the system, however, becomes slightly degraded. The sending user 4-3 may request on form 30 completed in step 101 (FMLR; MSSG) the identification means 3 to store the contents of the registered message for a rather long period of time (for example one year) in the storage means 5 shown in Fig. 1. As a result, it is possible to ask the managing independent body for the complete contents and verify the contents in the case of a dispute between the sending user 4-3 and the receiving user 4-M. If the sending user 4-3 wishes to send a registered message to somebody who does not have a facsimile machine 2-1 ... 2-N, or is not an authorized user of the system, the registered message can be sent to a facsimile machine 8 belonging to an authority delivering the post, after the registered message has been sent to the identification means 3 and the sending user 4-3 has been identified. The authority delivering the post takes care of the delivery of the registered message and the identification of the receiving person according to the procedure customary with registered post. This authority informs, after completion, the identification means 3 that the registered message has been delivered to the receiving person who has identified himself as such. If the sending user 4-3 has so requested, the identification means 3 can send an acknowledgement of receipt to the sending facsimile machine 2-2 in the manner described with respect to Fig. 2. The description given here also clarifies that somebody who does not have a facsimile machine 2-1 ... 2-N can send a registered message to the receiving user 4-M of the system according to the invention via a post delivery service. After the sending person has identified himself at the office of the post delivery service, the message is sent to the identification means 3 which identify the receiving user 4-M in the manner described with respect to Fig. 2 and deliver the registered message. Alternatively, it is possible to equip a data bank with the identification means 3 according to the invention. This enables a user 4-1 ... 4-M of a facsimile machine 2-1 ... 2-N to send registered facsimiles and obtain in above manner proof of the sending of this message. It is likewise possible to request in above manner personal data from a data bank per facsimile, which data are directly sent to the user 4-2 after step 111 (RCV; CNTRL) in Fig. 2 by the identification means 3. The further steps of Fig. 2 are then omitted. Fig. 5 shows another embodiment for the identification means 3. These identification means 3 comprise a memory 5, an electronic reading system 9, a microprocessor 11 with a RAM 10 and a ROM 13, a clock generator 12 and a signal converter 14. The electronic reading system 9 sends address signals derived from the personal data to the microprocessor 11 which stores these signals in the RAM memory 10. The message to be sent can be stored in memory 5. The microprocessor 11 thereto sets a switch S 1 in the position shown. For determining the USREQ signal, the microprocessor reads the address signals from the ROM memory 10, a time and date signal from the clock generator 12, as required, and generates the user request signal USREQ on the basis of the first algorithm stored in ROM memory 13. This algorithm can be the algorithm used in the Digipass® products of Digiline. This USREQ signal is converted in the signal converter 14 to facsimile signals and sent to the sending user 4-3. Such a signal converter 14 may be, for example, the Intel SatisFAXtion® Modem/200 by Intel, which contains Intel SatisFAXtion® software. In addition, the microprocessor 11 computes the USID signal and stores this signal in RAM memory 10. Accordingly, the microprocessor 11 generates and sends out a USREQ signal for the receiving user 4-M. The USID signals coming from users 4-1 ... 4-M are applied to the microprocessor 11 by the electronic reading system 9. This processor will verify the identity of the users 4-1 ... 4-M in response to the received USID signal and the USID signal stored in the ROM memory 10. If information about the received message is necessary to generate the USREQ signal, the microprocessor 11 may directly access a received message by setting switches S1 and S2 in the position not shown. Alternatively, it is possible to read this message from memory 5 by setting switch S2 in the position shown if the message was stored there. For the purpose of verification, the message can be similarly read from memory 5 and sent to a user. The encrypting of a message with the secret key SK is carried out in the microprocessor based on a second algorithm stored in the ROM, for example, the RSA or DSA algorithm known per se for cryptographic purposes. Finally, this message is sent out via the signal converter 14. Fig. 6 shows the personal list of an authorized user of the system. The drawing Figure shows USREQ signals in the left column and the associated USID signals in the right column.

Claims: A certification method for facsimile devices in a telecommunication system comprising at least a sending facsimile device, a receiving facsimile device and an independent body, in which certification method at least the contents of a facsimile message and/or the moment of transmission of the facsimile message and/or a transmission event are certified by a digital signature and an unforgeable receipt or certificate in machine readable form is provided by the independent body and in which certification method users of both the sending and the receiving facsimile device are identified by the independent body. A method as claimed in claim 1, wherein the unforgeable receipt or certificate has an easy user perceptible form, if the user is a human being. A method as claimed in claim 1, wherein a user identification signal is processed so as to identify a user of the facsimile device. A method as claimed in claim 1, wherein a received facsimile message is archived after certification. A telecommunication system comprising a least a sending facsimile device, a receiving facsimile device and an independent body, certification means for certifying at least the contents of a facsimile message, and/or the moment of transmission of the facsimile message, and/or a transmission event, by a digital signature and an unforgeable receipt or certificate in machine readable form is provided by the independent body, the system further comprising identification means managed by the independent body for identifying users of both the sending and the receiving facsimile device.

Inventors: MARECHAL GUY NOEL LEON JOSEPH, MARECHAL, GUY NOEL LEON JOSEPH, Marechal, Guy Noel Léon Joseph
Applicants: KONINKL PHILIPS ELECTRONICS NV, KONINKLIJKE PHILIPS ELECTRONICS N.V.
Application year: 1994
Main classification: H04N1
IPC codes: H04N1, H04L29